HD MKV Playback is slightly jerky

**turumbar** · December 19th, 2009, 09:38 AM

I have noticed a difference in quality of the playback of HD MKV's in the Boxee Beta compared to the Alpha. I have tried several of these files, and there is just enough jerk in the motion to be noticeable. It isn't horrible, but it is noticeable, and it is an issue that wasn't present in the alpha.

OS: Windows 7 Enterprise 64
Processor: AMD Athlon 64 X2 5200 Brisbane 2.7GHz 2 x 512KB L2 Cache Socket AM2 65W Dual-Core Processor
Ram: G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit
Mobo: Asus M3N78-EM
Video: onboard HDMI

**judgeschambers** · December 19th, 2009, 09:46 AM

I've noticed it too. I have a true HD 1080p 24fps MKV file and it too is jerky in Beta. Plays perfectly on my Revo using MPC-HC media player.

I am assuming that GPU hardware acceleration is not yet fully implemented for this file type in Beta. Hopefully soon.

**jbras** · December 24th, 2009, 01:01 AM

While I have noticed the odd bout of jerkiness that wasn't there in the alpha (even in 720p files), I have another problem that bothers me more with mkv playback.

I find that I'm getting a noticeable amount of artifacting in mkv files that wasn't there in the alpha, or when I play the identical files in Windows Media Player.

Has anyone else experienced this?

By the way, I'm running this using my laptop with integrated Intel graphics (g4500). Drivers all up to date.

**judgeschambers** · December 24th, 2009, 06:38 AM

Well, this is the thread to note these issues, so it is noted now.

This could be a DX issue or something too with the hardware or the software.

For me on my set ups, mkv's work fine. Lucky I guess.

**akshunj** · December 26th, 2009, 10:32 PM

From the release notes:

"Boxee can now accelerate decoding of H.264 videos using compatible graphics processing units (GPU). This means that machines with slower CPUs (such as Intel Atom) can now play high-definition content! This functionality is only available on Windows Vista and Windows 7 and a compatible video card."

Go here for a list of supported cards:
http://www.boxee.tv/download/relnotes?ver=0.9.20

As a Linux user, I'm out of luck for vdpau acceleration at this point. I get mostly smooth 720p playback, but as I'm using the ION nettop, any multitasking at all will rapidly degrade performance. Hopefully this will be fixed soon as it was part of the alpha.

It also looks like WinXP is out of the loop also. And the list of supported video cards is short. I'm sure this will all be beefed up soon...

--Akshun J

**turumbar** · January 9th, 2010, 07:31 PM

The M3N78-EM uses an onboard geforce 8 series video processor. The issue I am experiencing was never present in the alpha (which I ran almost a year). Even after updating to the most recent version of the beta, this is still an issue for me. On this machine, I can play the file in another program fullscreen (such as vlc) and I have no playback issues.

Once again. This isn't something that is a huge glaring problem. It is just in HD MKVs. It isn't artifacting or anything like that. When there is fast action in the video file, or even quick pans, it is almost as if the movement of the camera is jerky.

I hope this issue is being looked at. Even my five year old daughter knows how to navigate boxee. We use it in my house everyday, and if this one issue is fixed, for me it would be flawless.

**edit**

I wanted to add if there is any information that I can give to help contribute to this being solved, do not hesitate to ask. If it will help the community in anyway, I'd love to assist.

**dauger** · January 22nd, 2010, 05:55 PM

Adding a "me too": I've seen similar jerkiness on boxee-0.9.11.5591, boxee-0.9.14.6992, and boxee-0.9.20.10261 on my Mac mini dual-core 2.26GHz 2GB RAM running Mac OS X 10.5.8. I'm convinced that the hardware and OS can handle it because Plex 0.5.8 successfully plays back HD MKV with zero issues. These MKV's were generated via MakeMKV from Blu-Ray titles (that I own!) like Star Trek, the Matrix trilogy, Contact, etc.

I like boxee's GUI more than Plex's GUI, so I'm sad to say I'm using Plex instead of boxee until I find a version of boxee that plays back HD MKV's steadily.

**monkeykiller** · January 23rd, 2010, 09:59 PM

I had heavy artifacting in the Beta, but had none of those problems in the alpha. Disabling hardware acceleration fixed all the video playback issues I was having.

**turumbar** · January 26th, 2010, 10:34 PM

Dauger, Monkeykiller's fix worked for me as well. I had no artifacting, but I did have that slight jerk. I find it odd that unchecking hardware assisted decoding would fix it. The onboard graphics card my mobo uses definitely benefits from hardware acceleration for bluray playback. Every issue I had disappeared once I unchecked this though. In more recent beta builds, embedded subs stopped appearing in my mkv's as well. Unchecking that box fixed that issue as well. I don't know if there are still issues to be resolved by the devs on this, but for now, I am happy with boxee once more

**judgeschambers** · January 27th, 2010, 06:05 AM

Update:
Full 1080P 24 fps HD mkv files are not currently supported with GPU acceleration in Boxee Beta. They will by laggy and stutter. There have been more than a few DX issues as of late. So,It is slated to be worked into a future build.

I'll have to test Monkeykiller's fix, though that would cause all flash and silverlight to not be accelerated, which is most of my viewing types.

As a side note, 720p files seem to play well as long as your CPU can handle the file in boxee.